The current state of the art technology in the field of optical fiber connectors does not make it easy for technicians working in the field to install or repair optical connections. There are generally two types of connectors, namely fusion connectors and mechanical connectors.
In the case of fusion connectors, the two fiber ends to be coupled are mounted in an instrument that allows for the precision alignment of the two fibers adjacent to one another with their respective cores in alignment. At this point, sufficient heat is provided to melt and fuse the cores together. During the fusion process, a number of problems can arise that will result in poor optical connection between the fibers, such as misalignment between the fiber cores as a result of the heating process or even a failure of joining of the two cores during the heating process. The failure rate of making a fiber connection using fusion in the field is often greater than 50%.
In the case of mechanical connectors, it is common in many types of connectors to place the fiber ends in a single “V” groove on a substrate in end-to-end abutment and then to build a packaging around the fibers with the use of optical gels and/or adhesives to complete the connection. When the fibers are not of the same diameter, the alignment of fibers in a groove in a substrate is not good. With conventional mechanical splicing technology, the chances of assembling a successful connection in the field can be about 1 in 3.
A mechanical splice for optical fibers that provides an easier way to connect fibers with greater rates of success than the rate of success associated with the previous state of the art has been developed by the Applicants of the present invention. In U.S. patent application publication 2005/0220418 published on Oct. 6, 2005, based on PCT/CA03/00232 published as WO 2003/071328, there is disclosed a mechanical splice made of shape memory alloy construction having an axial passageway or conduit that is expandable to receive an optical fiber end. The splice can then exert a moderate radial pressure to retain the optical fiber securely centered in the axial passageway and ensure an end-to-end coupling between two optical fiber ends.
Such technology however requires special tooling for opening and closing the axial passageway in order to controllably secure and release the optical fiber ends to provide the desired optical coupling. Examples of instruments adapted to allow the controlled expansion and contraction of the axial passageway in the mechanical splice is known from Applicant's own previous PCT publications, WO 2004/015473 published Feb. 19, 2004 and WO 2005/040876 published May 6, 2005.